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Recently established, temperate tree populations combine a high level of differentiation for adaptive traits, suggesting rapid genetic evolution, with a high level of genetic diversity within population, suggesting a limited impact of genetic drift and purifying selection. To study experimentally the evolutionary forces in a recently established population, we assessed the spatial and temporal patterns of genetic diversity within a disjunct population of Cedrus atlantica established 140 years ago in south-eastern France from a North African source. The population is expanding through natural regeneration. Three generations were sampled, including founder trees. We analysed 12 isozyme loci, three of which were previously found in tight association with selected genes, and quantitative traits. No bottleneck effect was detected in the founder generation, but a simple test of allelic association revealed an initial disequilibrium which disappeared in the following generations. The impact of genetic drift during secondary evolution was limited, as suggested by the weak temporal differentiation. The genetic load was not reduced after 3 generations, and the quantitative variation for adaptive traits did not change either. Thus, initial genetic changes first proceed from a rapid re-organisation of the diversity through mating and recombination, whereas genetic erosion through drift and selection is delayed due to temporal and spatial stochasticity. Two life-history traits of trees contribute to slowing down the processes of genetic erosion: perenniality and large spatial scale. Thus, one would expect recently established tree populations to have a higher diversity than older ones, which seems in accordance with experimental surveys.Heredity (2004) 93, 542-550. doi:10.1038/sj.hdy.6800549 Published online 18 August 2004 [ABSTRACT FROM AUTHOR]

Rabies is one of the risks to which travelers are exposed when going abroad. During the summer of 2012, a rabid dog died in an International Military Transit Camp in Afghanistan, leading to a public health investigation briefly reported here. The lessons learned from this episode are that such investigations are complex and that information for travelers needs to be improved., (© 2013 International Society of Travel Medicine.)

We investigated the variation and short-term evolution of the selfing rate and inbreeding depression (ID) across three generations within a cedar forest that was established from admixture ca 1860. The mean selfing rate was 9.5%, ranging from 0 to 48% among 20 seed trees (estimated from paternally inherited chloroplast DNA). We computed the probability of selfing for each seed and we investigated ID by comparing selfed and outcrossed seeds within progenies, thus avoiding maternal effects. In all progenies, the germination rate was high (88-100%) and seedling mortality was low (0-12%). The germination dynamics differed significantly between selfed and outcrossed seeds within progenies in the founder gene pool but not in the following generations. This transient effect of selfing could be attributed to epistatic interactions in the original admixture. Regarding the seedling growth traits, the ID was low but significant: 8 and 6% for height and diameter growth, respectively. These rates did not vary among generations, suggesting minor gene effects. At this early stage, outcrossed seedlings outcompeted their selfed relatives, but not necessarily other selfed seedlings from other progenies. Thus, purging these slightly deleterious genes may only occur through within-family selection. Processes that maintain a high level of genetic diversity for fitness-related traits among progenies also reduce the efficiency of purging this part of the genetic load.

Unlabelled: Less-lethal rubber-bullet weapons are designed to induce blunt injuries that incapacitate violent individuals., Aim and Scope: We intend to study the functional and aesthetic impairments and the cost in terms of social health resulting from rubber-bullet facial trauma., Materials and Methods: We retrospectively collected all the facial trauma cases caused by mass-appeal, less-lethal guns followed up in two French university hospitals since the year 2000. We did not consider the facial injuries caused by professional, less-lethal, rubber or plastic bullet guns., Conclusion: We showed that mass-appeal, less-lethal rubber-bullet guns induce severe traumas with irreversible functional consequences and long-term social implications. Victims of facial rubber-bullet traumas should be managed like high-energy trauma patients and benefit from extremely careful primary wound care.

Purpose: To determine the impact of a joint PACS implementation at a university medical center and cancer center on the radiology practice profile. Materials and methods. In 5 radiology sections, patients, selected based on identifiable acute or chronic diseases, underwent US, CT or MRI. Data were collected on datasheets from each provider with regards to clinical history, availability of prior examinations, description of patient management during the different phases of the examination, duration of examinations, and satisfaction. Data obtained prior to PACS implementation and 6-12 months and 30-36 months after implementation were compared., Results: A total of 1098 datasheets were collected. Hard copy readings rapidly decreased. Comparison with prior examinations improved (+20.6% to 25.6%) as well as frequency of post-processing (+29%). The time required for image management was much more reduced for technologists (-75%) than for physicians (-23%). PACS implementation only temporarily improved the availability of radiology reports and the distribution of work between senior and junior radiologists. User satisfaction, initially high, progressively decreased due to saturation of the archival capabilities., Conclusion: PACS implementation in a large university center improves the efficiency of image acquisition but does not solve some of the inefficiencies of hospital organization.